Automatic gun.



G. T. BUCKHAM.

Y AUTOMATIC GUN.

APPLICATION m2o JUNE s. me.

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G T. BUCKHAM.

AUTOMATIC GUN.

APPucATlon man lune 8. 1916.

3 SHEETS-SHEET 3- 1 ,262, 1 69. Patented Apr. 9, 1918.

.-f-fa x i n f i C 7,7/ /I J J I 6 f lUJeIZZLz? provements AUNITED STATES PATENT OEEIOE.

GEORGE THOMAS BUCK'HAM, OF WESTMINSTER, LONDON, ENGLAND, ASSIGNOB T0 .VICKERS LIMITED, OF WESTMINSTER, ENGLAND.

AUTOMATIC GUN.

Specication of Letters Patent.

Patented Apr. 9, 1918.

Application mea :une 8,1916. serial ne. 102,435.

To all 'whom it may concern: Y

Be it known that I, GEORGE THOMAS BUCK- HAM, a subject of the King of Grreat` Britain, residing at Vickers House, Broadway, Westminster, in the county of London, England, have invented certain new and useful Imin or Relating to Automatic Guns, of which the following is a specilication..

' recocking of the striker i clearly understood eiect will describe the same more fully `This invention relates to automatic gulls of the kind in which the lock is operated by toggle levers comprising acrank and a side lever. In such guns it is usual, through the intermediary of an arm on the tumbler cooperating with the said side lever, to cock the striker during the bending of the toggle levers (whether the gun is operated manually or automatically) the tumbler in such case being angularly displaced to force the striker to its rearmost position past the safety sear bent just as the crank is passing the vertical position. AThis action, owing to the return movement of the crank to the vertical position, again retracts the striker, temporarily removing it from the safety 4sear bent and causing what is known asjrecocking. This is disadvantageous as it results in an undue weakening of the striker spring, and also results in a lack of smoothness in nism; the chief object of the invention is to provide improved means whereby the striker will be cocked during the rearward movement of the lock butv will not be retracted during the forward movement of the lock so as to avoid the aforesaid recocking of the striker.

According to the invention, the cover of the n mechanism casing is provided with a tripping piece against which the tumbler comes lock, to displace the tumbler and cock the striker, theA said tumbler having an arm by which it can also bedisplaced by the side lever to cock the striker in the usual manner when the lock is operated by hand with the cover open. The tumbler may be provided with an upwardly projecting extension for engagement with the aforesaid tripping piece on the cover. j

In order that the said inventlon may be andreadilyv carried. mto

the working of the mecha-- during the rearward travel of the.

with reference to the accompanying drawing, in which Figures 1 and 2 are sectional side elevations showing the lock mechanism of an automatic gun provided with a constructlonal form of my improvements, Fig. l showing the parts in the position they occupy when the barrel has partly recoiled and Fig. 2 showing the position they occupy when the barrel has fully recoiled. Fig. 3 is a plan of the lock mechanism (with the cover of the mechanism casing removed) showing the position of the parts when the barrel and the lock are in the forward or firing position; and Fig. 4 is a section taken approximately on the line X, X of Fig. 1 looking in a forward direction, the cover of the Imechanism casing being shown in full lines in its closed osition and in broken lines in its open position. Figs. 5, 6 and 7 are diagrammatic views sition of the lever, which moves the cartridge carrier downwardly, with relation to the side cams and the cartridge carrier, the

showing the porecoiled posltlon, the barrel returning after recoiling and the barrel approaching its forward position.

A is, the lock, A the crank, 1, the recoiling barrel, 2, the cartridge carrier movably mounted in the lock A, and A3 the side lever. The crank A is pivotally connected by the shaft C2 to an extension 3 on the barrel, and the side lever A3 is connected at one end to the crank, and at the other end to the lock. 4, 21 are the side cams which coperate with horns on-the cartridge carrier 2. B- 1s the tumbler, B the Striker, B2 the safety sear and B3 the trigger Sear. C is the mechanism casing cover and C is the trlppmg piece thereon w1th which an extenslon on the tumbler engages during the rearward movement of the lock, to cock the striker.

As shown in the drawings, the crank A' has two downward extensions C carrying rollers C1, which, during the initial carrying movement of the barrel, coperate wlth fixed inclines b arranged on the side plates of the mechanism casing. These inchnes terminate at their rear in straight guides b" for the rollers. The stops b* for coperating with the projection Le on the crank A1 may be in Athe form of spring-controll plungers, as shown in Fig. 1 of the ldrawing. After the toggle joint has been initially bent by the coperaton of the inclines b" with the rollers C, the continuous rearward movement of the crank shaft C2 carries the projections c into contact with the beveled faces on the spring plungers bx,

. turn spring (not shown), the front faces ofl which plungers are displaced against thel resistance of their springs to enable the projections c to pass behind them. On the forward movement of the barrel taking place under the iniuence of its rethe .projections o -coperate with the rear faces of the plungers bX without lifting thev latter, and the barrel moves forward without the lock A, the crank A being further 'angularly displaced. At the same time,

ving the latter, and the barrel moves forward without the lock A, the crank A being further angularly displaced. At the same time, the aforesaid cams/4, 4, upon which the horns 7 on the carrier have been resting (see Figs. 5,-7), move clear of these horns, and the carrier is then moved downn wardly by the'lever-s, which, as aforesaid, are pivoted to the mechanism casing and controlled by the cam surfaces 6 on the side cams 4, 4. The crank A i's also formed with arms 8 which coperate with the straight portions bX of the inclines on the side plates of the mechanism casing to prevent overthrow of the crank. When the projections o move clear 'of the plungers bx (Fig. 1), the spiral sprmg inclosed in the ca sing'cx causesthe crank A to move the lock toward its forward position bythe straight-v ening' of the toggle levers.

,The mechanism casing carries the springcontrolled pivoted pawl 9 which, in the event of the recoil movement of the barrel being insufficient to enable the horns ofthe carrier 2 to become cl'ear of the cams 4, 4, j

. will lie in the path of the upper portion of the carrier," and thus prevent the lock from being moved forward, thereby avoiding the possibility of the cartridge in the belt being -fired by the impact with `them of the nose of i the cartridge'in the carrier.

The4 shaft C2- of the crank is provided Vwith. a handle C2, by means of which the breech mechanism can be Imoved into the open position by hand; in this event, as the side cams 4, 4 for controlling the carrier are attached to the barrel extension, which is then stationary, the improved mechanism operates in substantially the same ,manner as that of the automatic guns at present in use when operated by hand.

When the lock A is moved rearward automatically a roller on the arm b comesv against the aforesaid tripping piece C', and is thereby displaced into the position shown by Fig. 1, to retract the striker B into engagement first with the trigger sear B3 and then immediately afterward with the safety sear 132. When this operation has been com- 'pleted the roller on the arm b moves clear crankA and the side lever A3 resume their straightened position the said side lever dis# engages the safety sear B2 from the striker because of the fact that the portion 10 engages thev end 11 of the safety Sear to move thelatter downwardly as is well understood and permits the striker to advance slightly until arrested by vthe trigger sear B3. In Fig. 1, the maximum anglereached by the side lever is indicated by chain lines and from this it will be seen that this side lever does not operate upon the tumbler. A similar/ action toY that described above occurs when the lock is operated by hand instead of automatically.l It will therefore be obvious that so long as the cover is not opened the cocking of the striker will be effected by the tumbler coperating with the tripping piece, whether the gun beoperated'auto- 'matically or manually.

When however, thev lock being o erated by hand with the cover raised the a oresaid tripping piece C is not available to operate the tumbler B which is thendisplaced to`I cock the striker by the side lever As through the intermediary of the arm b on the tumbler, the parts being so constructed and arranged that the striker will be retracted only suiiiciently to enable the trigger sear. B3 to enga e with its bent on the striker, and there ore not suiiiciently to enble the safety Searl B2 to engage with its ent.

The means for actuating the trigger Sear B3 to release the striker comprises a pivoted member B4, which is adapted to engage with the said Sear. vThis pivoted-member, when the parts are moved forward, or into their ring positions, bears against a projection 12 on the casing ofthe mechanism. Thus,

the trigger will be actuated at the proper time.

. What I' claim and desireto secureby Let-- ters Patent of the UnitedStates iis:-

1.. In an automatic gun, Y. the combination the lock, the barrel lever, the striker,

striker during the manual operation of the lock when the movable cover is open, and

means carried by said cover for cocking said striker when the cover is closed.

2 In an automatic gun, the combination of the mechanism casing, its movable cover, the lock, the toggle levers for operating the lock, the striker, the tumbler which cocks said striker during the manual operation of the lock with the movable cover open and which has an arm bearing against one of the toggle levers, and a tripping piece which is mounted i onY said movable coverY and serves to displace the tumbler and cock the striker during the rearward movement of the lock when said cover is closed.

3. In an automatic gun, the combination of the mechanism casing, its movable cover, extension, the operating said extension, the side the tumbler which cocks said striker during the manual operation of the lock with the movable cover open and which has an arm bearing a ainst said side lever, and a tripping piece w 'ch is mounted on said movable cover and serves to displace crank pivoted to the tumbler and cock the striker during the rearward movement of the lock when said cover is closed.

4. In an automatic gun, the combination of the mechanism casing, its movable cover, the lock, the barrel extension, the operating crank pivoted to said extension, the side lever, the striker, the safet Sear and the trigger sear for engaging with said striker, the tumbler which cocks said striker into engagement with the trigger sear during the manual operation of the lock with the movable cover open and which has an arm bearing' against said side lever, and atrippmg piece which is mounted on said movable cover and serves to displace the tumbler and cock the striker into engagement with the safety sear during the rearward movement. of the lock when said cover is closed.

In testimony whereof I aix my signature in the presence ef two witnesses.

' GEORGE THOMAS BUGKHAM.

Witnesses:

JNO. R. CAswELL, GLADYS M. BAnDaN; 

